This example creates a full-screen SVG pattern of 100 alternating horizontal and vertical stripes, with both sets masked to reveal a circular focal point in the center. Using D3’s `select` and `range` utilities, it generates rectangles that are constrained by two custom masks—one that hides everything outside the circle and another that hides the circle itself—producing a grid-like intersection effect. The rendered output is purely geometric, relying on SVG masks rather than data.